import io
from pathlib import Path
import pandas as pd
import pytest

from excel_import.reader import ExcelReader
from excel_import.config import SheetConfig


@pytest.fixture
def xlsx_file(tmp_path: Path) -> Path:
    path = tmp_path / "test.xlsx"
    df = pd.DataFrame({
        "Artikelnummer": ["A001", "A002", "A003"],
        "Bezeichnung": ["Widget", "Gadget", None],
        "Preis": [9.99, 14.50, 0.99],
    })
    df.to_excel(path, index=False)
    return path


def test_sheet_names(xlsx_file: Path):
    reader = ExcelReader(xlsx_file)
    assert reader.sheet_names() == ["Sheet1"]


def test_read_basic(xlsx_file: Path):
    reader = ExcelReader(xlsx_file)
    df = reader.read(SheetConfig(sheet=0, target_table="t"))
    assert len(df) == 3
    assert list(df.columns) == ["Artikelnummer", "Bezeichnung", "Preis"]


def test_read_drops_empty_rows(tmp_path: Path):
    path = tmp_path / "empty_rows.xlsx"
    df = pd.DataFrame({"A": ["x", None, "y"], "B": [1, None, 3]})
    df.to_excel(path, index=False)

    reader = ExcelReader(path)
    result = reader.read(SheetConfig(sheet=0, target_table="t"))
    assert len(result) == 2


def test_read_column_rename(xlsx_file: Path):
    from excel_import.config import ColumnMapping
    cfg = SheetConfig(
        sheet=0,
        target_table="t",
        columns=[
            ColumnMapping(source="Artikelnummer", target="art_nr"),
            ColumnMapping(source="Bezeichnung", target="bez"),
            ColumnMapping(source="Preis", target="preis"),
        ],
    )
    reader = ExcelReader(xlsx_file)
    df = reader.read(cfg)
    assert "art_nr" in df.columns
    assert "Artikelnummer" not in df.columns


def test_read_column_skip(xlsx_file: Path):
    from excel_import.config import ColumnMapping
    cfg = SheetConfig(
        sheet=0,
        target_table="t",
        columns=[
            ColumnMapping(source="Preis", target="Preis", skip=True),
        ],
    )
    reader = ExcelReader(xlsx_file)
    df = reader.read(cfg)
    assert "Preis" not in df.columns


def test_read_ods(tmp_path: Path):
    pytest.importorskip("odf")
    path = tmp_path / "test.ods"
    df = pd.DataFrame({"Name": ["Alice", "Bob"], "Wert": [1, 2]})
    df.to_excel(path, index=False, engine="odf")

    reader = ExcelReader(path)
    result = reader.read(SheetConfig(sheet=0, target_table="t"))
    assert len(result) == 2
    assert list(result.columns) == ["Name", "Wert"]


def test_file_not_found():
    with pytest.raises(FileNotFoundError):
        ExcelReader("/nonexistent/path/file.xlsx")


def test_unsupported_extension(tmp_path: Path):
    f = tmp_path / "data.csv"
    f.write_text("a,b\n1,2")
    with pytest.raises(ValueError, match="Unsupported"):
        ExcelReader(f)